Thermally induced band gap increase and high thermoelectric figure of merit of n-type PbTe

Abstract

Unlike in many other semiconductors, the band gap of PbTe increases considerably with temperature. We compute the thermoelectric transport properties of n-type PbTe from first principles including the temperature variation of the electronic band structure. The calculated temperature dependence of the thermoelectric quantities of PbTe is in good agreement with previous experiments when the temperature changes of the band structure are accounted for. We also calculate the optimum band gap values which would maximize the thermoelectric figure of merit of n-type PbTe at various temperatures. We show that the actual gap values in PbTe closely follow the optimum ones between 300 K and 900 K, resulting in the high figure of merit. Our results indicate that an appreciable increase of the band gap with temperature in direct narrow-gap semiconductors is very beneficial for achieving high thermoelectric performance.

10 pages, 9 figures

References in corpus (9)

• Towards predictive many-body calculations of phonon-limited carrier mobilities in semiconductors
• Electron-Phonon Scattering in the Presence of Soft Modes and Electron Mobility in SrTiO${}_3$ Perovskite from First Principles
• Phonon-limited resistivity of graphene by first-principle calculations: electron-phonon interactions, strain-induced gauge field and Boltzmann equation
• Dominant electron-phonon scattering mechanisms in $n$-type PbTe from first principles
• Limit of zT enhancement in rock-salt structured chalcogenides by band convergence?
• Temperature effects on the electronic band structure of PbTe from first principles
• Broadband Phonon Scattering in PbTe-based Materials Driven Near the Ferroelectric Phase Transition by Strain or Alloying
• Emphanitic anharmonicity in PbSe at high temperature and the anomalous electronic properties in the PbQ (Q=S, Se, Te) system
• Acoustic Deformation Potentials of $n$-Type PbTe from First Principles

Cited by in corpus (6)

• Electron-phonon scattering and thermoelectric transport in $p$-type PbTe from first principles
• Temperature induced band convergence, intervalley scattering and thermoelectric transport in p-type PbTe
• Towards temperature-induced topological phase transition in SnTe: A first principles study
• Effect of spin-orbit coupling on the zero-point renormalization of the electronic band gap in cubic materials: First-principles calculations and generalized Fröhlich model
• Electron-phonon coupling and electronic thermoelectric properties of n-type PbTe driven near the soft-mode phase transition via lattice expansion
• Generalized deformation potential and machine-learning approaches for electron-phonon coupling and thermoelectric transport in semiconductors